Lighter for burners



Dec. 15, 1931. D, F. MCFARLAND ET AL LIGHTER FOR BUR'NERS Filed March14, 1927 3 Sheets-Sheet ff 47 /8 d'1* W www W RA n eAD r .UW a NME Es/ra Dec. l5, 1931. D. F. MCFARLAND ET AL 15836268 LIGHTER -FOR BURNERSFiled March 14, 1927 3 Sheets-Sheet 2 2 OFF 2N /44 /43 49 /45 W 4o y 398 35 a6 IzefzZ-ons DALE EMCFARLAND y REX E. DAV/S Dec. 15, 1931. D. F.MGFARLAND ET Al.

LIGHTER FOR BURNERS 3 Sheets-Shed 5 Filed March 14. 1927 Z'zenjors DALEl-TMCFARLAND REX E. DAVIS Patented' Dec. 15, 1931 .dan frf DALE F.inrcFAJaLAND.,f or niNNEAroLIs. AND anx E. DAvIs, or ANoKA, MINNESOTA,AssIGNoBs rro ANDREW E. cAmsEN, or mNNnAnoLIs, MINNESOTA LIGHTER FORBURNERS tltus, and the primary object is to provide means of a novel,efiicient and practical nature for lighting such burners when they areeither manually or automatically supplied with fuel at'regular orirregular intervals 10.A further and more specific object is to providemeans, of a primary nature, for lighting a series of burners in anapparatus, such as a boiler, and in combination therewith to providemeans of a secondary nature, for

first lighting the primar means. A further object is to provide arunning pilot, for lighting the main burners, a permanent pilot, forlighting the running pilot, and means associated with the main fuelsupply valve of the burners, for automatically lighting the runningpilot immediately or shortly before supplying the fuel to the mainburners, and, as soon as the main burners thus become lighted by therunning pilot ,to extinguish the running pilot, until the main burnersare to again be lighted. A further object is to provide thermallyinfiuenced means, in conjunction with the lighter, for electricallydisconnecting a temperature-control thermostat, whereby such thermostatIwill be rendered ineffective to start the flow of fuel to the mainburners in the event that the pilot .burner should become accidentallyextinguished. Still further and more specific objects will be disclosedin thel course of the following specification, reference being had tothe accompanying drawings, wherein:

Fig. 1 is a planiview, partly in section,

illustrating the application of my invention to a boiler having, aplurality of gas burners.

Fig. 2 is a sectional elevation as seen on the line 2-2 in Fig. 1.

Fig. 3 is a sectional elevation on the line 3--3 in Fig. 2.

Fig. 4 is a-sectional elevation on'the line 4-4 in Fig. 2.

Fig. 5 is a sectional elevation as on the,

the nia-in burners B. The

line 5 5 in Fig. 1, but with various portions broken away for purpose ofillustration.

Fig. 6 'is an enlarged detail view of the pilot burner.

F ig. 7 is a diagrammatic view of the electrical circuit connections.

Referrin to the drawings more particularly and y reference characters Adesignates the walls of a boiler having a series of burners B which aresupplied with as (or other fuel) by a main supply pipe The fuel to theburners is controlled by a valve D, in the pipe C, this valve has a head9, which is normally and yieldingly held closed by a spring 10, and isopened by the depressing of a stem 11 which extends upwardly through abrushing 12 in the neck of the valve.

Connected with the pipe C, and in advance of the valve D, is a plpe E,having a valve F, for controlling the supply of fuel to the runningpilot pipe E1. The valve F is similar to but smaller than the valve D,and has a head 13 which is yieldingly closed by a spring 14 and isopened by depressing its stem 15. The tube or ipe E1 extends into theboiler and passes adJjacent to the ends of all the burners B so as to bein a lighting position with respect to them. And for this purpose it isprovided with a series of perorations 16-throu h which the gas escapesto form a longitudinal series of pilot flames. The first of these flamesis started, when the valve F is opened, b a continuously or permanentlylit pilot, then, because of the closeness of the perforations 16, theflames will spread from one to the other until they reach the end of thepipe, thus 'ving a travelling or running action to ie pllot flamescreated by the perforations 16. The pilot Gis preferably provided with aBunsen tip which extends just within the wall A far enough to ignite thenear end of the running pilot El, but is preferably arranged almostentirely outside of the wall so as to be removed from the destructiveeffect of pilot G is connectedby `a tube 17 to the inlet side of thevalve F,.,so as to be continuously su plied with fuel,y 'and is providedwith a valve 18 `sus whereby the size of the pilot flame may beregulated as may'be required.

A casing 19, having a hinged cover 20, incloses the projecting ends ofthe valve stems 11 and 15, and is preferably secured to the necks of thevalves D and F, as is also a bracket 21 which supports a motor 22. Thismotor may be of any suitable design, but is preferably a spring motorsuch as is commonly used to operate dampers and valves in connectionwith temperature control electric thermostats, wherein predeterminedmaximum and minimum temperatures will close circuits which will in turnpermit or cause the motor to effect a predetermined movement. In thepresent instance, the shaft 23, of the motor 22, is so operated that foreach time the motor is affected by a thermostat the shaft will describea one-half rotation, and these semirotations are successively made inthe same direction. The shaft 23, of the motor, drives a shaft 24,journaled in the casing 19, and is connected to this shaft by aninsulated universal joint 25. The motor 22 is also insulated from thebracket 21, as at 26, so that electricity to the motor will not begrounded.

The valves D and F are respectively opened by a pair of levers 27 and 28which act on the stems 11 and 15. These levers are pivoted, as at 29,and are normally held down by springs 30, Which springs are strongenough to depress the stems 11 and 15 against theresi'stance of thesprings 10 and 14 when the levers 27 and 28 are free for such movements.The levers 27 and 28 are raised, so as to effect intermittent openingand closing of the valves, by a pair of cams 31 and 32 which are rigidon and rotate with the shaft 24.

As previously indicated, for each complete movement of the motor 22 theshafts 23 and 24 are turned one half a revolution. Conscquently the cams31 and 32 will have two distinct positions. The first or primarypositions of the cams is illustrated in Figs. 2, 3 and 4, and bothvalves D and F are closed, with a result that neither the main burners Bnor the running pilot E1 are supplied with gas. When the shaft 24 is nowpartly rotated, either manually or by the thermostatically influencedmotor 22, it will be seen (Fig. 3) that the cam 32 will release thelever 28, thus opening the valve F and supplying gas to the runningpilot El, which is then immediately lighted by the continuously burningpilot G. A continued movement of the shaft 24 now releases the lever 27from the end of the cam 31, thus causing the valve D to open andpermitting gas to flow to the main burners B, where it is ignited by therunning pilot El. This being done the function of the pilot El is, forthe time being, ended, and, as the shaft 24 approaches its F f f"secondary position as shown in F 1g. o, the

1,sse,aes

valve D is still open, but the cam 32 has again raised the lever 28 thusclosing the valve F. lYhen the room temperature has become raised to thedesired degree, and the motor 22 is again started, to extinguish themain burner, to rotate the shaft 24 a half revolution thus turning thecams 31-32 from their secondary positions, back to the initial positionsshown in Figs. 3 and 4. v

A safety device is provided in connection with the electric circuitsystem of the thermostatic control for the motor 22, and its object isto completely shut ofil the entire gas supply to the burners B and E1 ifand when the pilot G should become accidentally ex# tinguished at anytime. This device and its connection with the thermostat circuit may bedescribed as follows:

The thermostat, which is designated as 'I in Fig. 7. is of any commonand well known construction in which one circuit is closed when thetemperature of the room is raised to a predetermined degree. wherebysaid circuit will start. the motor 22 to close the gas supply to themain burner, and when the temperature has then fallen to a predeterminedminimum the thermostat will close another circuit which will influencethe motor to open the gas supply to the main burner. The motor has threeterminals 35. 36 and 37. the last of which is connected by a wire 38 tothe negative pole 39 of a battery or suitable source of current 40. Theterminals 35 and 36 are respectively connected by wires 41 and 42, tothe thermostat, and these wires designate or comprise the olf and oncircuits to the motor. Thus when circuit 41 is energized the motor isactuated so that the gas supply will be turned off, and when circuitV 42is energizcdthe gas 'will be on. The positive current of electricity isnormally supplied to the thermostat arm by a wire 43, extending from thepositive pole 44 of the battery 40 a wire 45, connected to thethermostat T, an a thermal switch S, which is normally closed andconnects the wires 43 and 45.

The thermal switch S comprises a bar or strip of bi-metal 46 which isrigidly secured at one end to the head end of the pilot tube G1. The bar46 is composed of two fused pieces of metal having differentcoeflieients of expansion whereby the bar, as a unit, will be distortedor bent upon being subjected to different or variable temperatures. Inthe present instance the bar is secured to and extends adjacent to thetube G1 and is conseqnently influenced by the pilot flame which, whenlit, keeps the tube G1 quite warm, but, it may here be noted, the bar 46is outside of the casing A so that it will not be inuenced by the moreintensive and destructive heat of the burners B and E1.

Under normal circumstances, i. e., with the pilot G burning, the bar 46being warmed, will be held in Contact with the terminal 47 of the wire45, but should the pilot G go out, so as to cool the tube G1, then thebar 46 will bend upward, breaking contact with 47, and making a newcontact with the terminal 48 of a wire 49 which connects with the wire41.

It will thus be seen that under normal circumstances the thermostat Twill be effective to actuate the motor to its on position, by virtue ofthe complete circuit 40, 44, 43, 46, 47, 45, T, 42, 36, 37, 38 and 39;and when affected by a rise in temperature the thermostat will beeffective to actuate the motor to its off position, by virtue of thecircuit 40, 44, 43, 46, 47, 45, T, 41, 35, 37, 38 and 39. When the pilotGis extinguished the Contact 46-47 breaks, and the positive current isno longer supplied to the thermostat which is thus rendered idle, with aresult that the gas cannot be again turned on until the pilot G is firstlit. This might be a dangerous condition, under certain circumstances,because if the circuit through S should be broken while the main burneris functioning then the thermostat would be ineffective to cut off thegas su pply when the maximum room temperature had been reached. Thiscontingency is provided for, however, in the branch circuit 48-49. Thus,under the conditions mentioned, the bar 46 will be bent up until itmakes a contact with the terminal member 48. There will then beacomplete circuit through the elements 40, 44, 43, 46, 48, 49, 41, 35,37, 38 and 39. which will influence the motor into turning the valves Dand F into-their closed positions. Relighting the pilot G willautomatically restore all the parts and circuits toY their initialconditions.

It is understood that suitable? modifications may be made in the generaldesign and structural details of the invention as herein shown,provided, however, that said modifications come Within the spirit andscope of the appended claims. Having now therefore fully shown anddescribed my invention, what I claim to be new and desire to protect byLetters Patent is:

1. The combination of a valve controlled main burner, a pilot forlighting the main burner, a thermal switch arranged to be influenced bythe pilot, a motor foropening and closing the valve of the main burner,a thermostat connected with said motor by two circuits one of whichincludes therein the thermal switch, said switch being adapted, upon theextinguishing of the pilot, to open one circuit to the thermostat andclose a direct circuit to the motor to thereby effect closing of thevalve.

2. The combination with a pair of yieldingly closed gas valves, one ofwhichcontrols the supply of gas to a series of main-burners and theother controls the supply offgas to a secondary burner, of a pair oflever acting members for opening the valves, and a pair of cams forcontrolling the movements of said levers one in advance of the other.

3. The combination with a pair of yieldingly closed gas valves one ofwhich controls the supply of gas to a main burner and the other controlsthe supply of gas to a secondary burner, of a pair o spring actuatedmembers normally tending to open thev valves, and means for controllingthe movements of said members.

4. The combination with a pair of yieldingly closed gas valves, one ofwhich controls the supply of gas to a main burner and the other controlsthe supply of gas to a secondary burner, of a pair of spring actuatedmembers normally tending to open the valves, and means for controllingthe movements of said members, comprising a pair of cams carried by arotatable shaft.

5. The combination of a main burner, a valve for controlling the supplyof fuel there to, a second burner for lighting the main burner andhaving a valve for controllingits fuel supply, both of said valves beingconnected to a common source of fuel supply, a pilot burner for lightingthe second burner when its fuel valve is open, and motor actuated means,operative in cycles, one cycle to successively open the valves of thesecond and first burners and and then close the valve of the secondburner, and the following cycle to close the valve of the first burnerwithout disturbing the closed condition of the valve of the secondburner.

6. In combination a main burner having a valve for controlling thesupply of fuel thereto, a second burner having a valve for controllingits fuel supply and arranged, when burning, to lightl the main burner, apilot burner for lighting the second burner, and temperature responsivemeans operative in successive cycles, for controlling the valves, andadapted, upon an initial cycle movement, to successively open the valveof the se "1 burner, open the valve of the main burner and then closethe valve of the second burner, and upon a succeeding cycle to close thevalve of the main burner without disturbing the closed condition of thevalve of the second burner.

In testimony whereof we affix our signatures.

DALE F. MCFARLAND. REX E. DAVIS.

